The present invention relates to steam temperature control of a combined cycle electric power plant, in general, and more particularly to combined and selective control of the gas turbine, afterburner and heat recovery steam generator so as to provide superheated steam for the steam turbine of a combined cycle electric power plant under predetermined steam flow, pressure and temperature operative conditions.
U.S. Pat. No. 3,973,391 (Reed and Smith) shows automatic and manual control of the inlet guide vane control apparatus of a gas turbine for modulated control as a function of load or inlet blade path temperature, in a combined cycle electric power plant. For the purpose of this description, U.S. Pat. No. 3,973,391 is hereby incorporated by reference.
U.S. Pat. No. 4010,605 (Uram) discloses a gas turbine control system in a combined cycle electrical power plant as part of an automatic start-up speed control involving fuel reference as a function of time. This patent refers to operation at a coordinated control level in which the settings of the fuel valves, the inlet guide vanes of the gas turbine and of the steam turbine throttle and bypass valves are coordinated to provide maximum plant efficiency at a given load level and optimum performance during load changing conditions. This patent is hereby incorporated by reference for the purpose of the present description of the invention.
U.S. Pat. No. 3,953,966 (Martz and Plotnick) shows a combined cycle electrical plant in which the heat supply from the gas turbine is reduced by placing a reduced load control signal thereon and by terminating the flow of fuel to the afterburner, whereby dry steam is recovered from the associated heat recovery steam generator. For the purpose of describing control of the gas turbine and afterburner in relation to the production of steam, U.S. Pat. No. 3,953,966 is hereby incorporated by reference.
U.S. Pat. No. 4,333,310 (Uram) discloses a combined cycle electrical power plant in which the afterburner is controlled as a function of the gas turbine exhaust temperature within a coordinated plant control for optimization of the afterburner operation. The U.S. Pat. No. 4,333,310 is incorporated by reference, in particular because it discloses the generation of afterburner setpoints in a coordinated mode of control with the heat recovery steam generator associated thereto.
U.S. Pat. No. 4,031,404 (Martz and Plotnick) discloses control of the gas turbine exhaust gas temperature to control the generated superheated steam temperature and pressure. The temperature of the gas turbine exhaust gases is sensed and the afterburner fuel supply valve is positioned in accordance wtih such sensed temperature to regulate the superheated steam temperature. The U.S. Pat. No. 4,031,404 is hereby incorporated by reference, thereby to include gas turbine control, afterburner control and heat recovery steam generator control in the present description.
U.S. Pat. No. 3,948,043 (Martz) discloses a combined cycle power plant in which the gas turbine and afterburner have coordinated fuel transfer.
U.S. Pat. No. 3,939,328 (Davis) shows adaptive process control for a combined cycle electric power plant, especially for boiler control therein. U.S. Pat. No. 3,939,328 is hereby incorporated by reference.
U.S. Pat. No. 4,168,608 (Uram) shows coordinated control between gas turbine, afterburner, heat recovery generator and steam turbine in a combined cycle power plant. U.S. Pat. No. 4,168,608 is incorporated by reference for that purpose.
U.S. Pat. No. 4,184,324 (Kiscaden et al.) discloses coordinated loading of the gas turbine and steam turbine and of operation of the afterburner in a combined cycle power plant. U.S. Pat. No. 4,184,324 is incorporated by reference for that purpose.